com.puppycrawl.tools.checkstyle.checks

Class FinalParametersCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.puppycrawl.tools.checkstyle.checks.FinalParametersCheck

All Implemented Interfaces:

Configurable, Contextualizable

public class FinalParametersCheck
extends AbstractCheck

Checks that parameters for methods, constructors, catch and for-each blocks are final. Interface, abstract, and native methods are not checked: the final keyword does not make sense for interface, abstract, and native method parameters as there is no code that could modify the parameter.

Rationale: Changing the value of parameters during the execution of the method's algorithm can be confusing and should be avoided. A great way to let the Java compiler prevent this coding style is to declare parameters final.

• Property ignorePrimitiveTypes - Ignore primitive types as parameters. Type is boolean. Default value is false.
• Property tokens - tokens to check Type is int[]. Default value is: METHOD_DEF, CTOR_DEF.

To configure the check to enforce final parameters for methods and constructors:

 <module name="FinalParameters"/>
 

To configure the check to enforce final parameters only for constructors:

 <module name="FinalParameters">
   <property name="tokens" value="CTOR_DEF"/>
 </module>
 

To configure the check to allow ignoring primitive datatypes as parameters:

 <module name="FinalParameters">
   <property name="ignorePrimitiveTypes" value="true"/>
 </module>
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• final.parameter

Since:

3.0

Nested Class Summary

Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

AutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field and Description
static String	MSG_KEY A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors

Constructor and Description
FinalParametersCheck()

Method Summary

Modifier and Type	Method and Description
int[]	getAcceptableTokens() The configurable token set.
int[]	getDefaultTokens() Returns the default token a check is interested in.
int[]	getRequiredTokens() The tokens that this check must be registered for.
void	setIgnorePrimitiveTypes(boolean ignorePrimitiveTypes) Setter to ignore primitive types as parameters.
void	visitToken(DetailAST ast) Called to process a token.

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck

beginTree, clearMessages, destroy, finishTree, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, init, isCommentNodesRequired, leaveToken, log, log, log, setFileContents, setTabWidth, setTokens

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

finishLocalSetup, getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverity

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

configure, contextualize, getConfiguration, setupChild

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MSG_KEY

public static final String MSG_KEY

A key is pointing to the warning message text in "messages.properties" file.

See Also:

Constant Field Values

Constructor Detail

FinalParametersCheck

public FinalParametersCheck()

Method Detail

setIgnorePrimitiveTypes

public void setIgnorePrimitiveTypes(boolean ignorePrimitiveTypes)

Setter to ignore primitive types as parameters.

Parameters:

ignorePrimitiveTypes - true or false.

getDefaultTokens

public int[] getDefaultTokens()

Description copied from class: AbstractCheck

Returns the default token a check is interested in. Only used if the configuration for a check does not define the tokens.

Specified by:

getDefaultTokens in class AbstractCheck

Returns:

the default tokens

See Also:

TokenTypes

getAcceptableTokens

public int[] getAcceptableTokens()

Description copied from class: AbstractCheck

The configurable token set. Used to protect Checks against malicious users who specify an unacceptable token set in the configuration file. The default implementation returns the check's default tokens.

Specified by:

getAcceptableTokens in class AbstractCheck

Returns:

the token set this check is designed for.

See Also:

TokenTypes

getRequiredTokens

public int[] getRequiredTokens()

Description copied from class: AbstractCheck

The tokens that this check must be registered for.

Specified by:

getRequiredTokens in class AbstractCheck

Returns:

the token set this must be registered for.

See Also:

TokenTypes

visitToken

public void visitToken(DetailAST ast)

Description copied from class: AbstractCheck

Called to process a token.

Overrides:

visitToken in class AbstractCheck

Parameters:

ast - the token to process